A, EF. Verrill—Mollusca of the New England Coast. 44] 
nearly parallel with it, though longer and more broadly rounded, 
passing insensibly into the curvature of the ventral margin; the en- 
tire margin is flat, beveled, and perfectly plain, with a simple but 
distinctly angulated inner rim. Externally the shell, when fresh, is 
covered with a thick, lamellose, and fringed, light yellowish brown 
epidermis ; over the central portion the epidermal processes are long, 
thin, and hair-like, and arranged in radiating lines; toward the mar- 
gin, especially ventrally and posteriorly, they become long, flat, thin 
and deeply lacerate or fringed at the end ; on the umbos the processes 
become small and ciliated with a distinct radial arrangement. 
Beneath the epidermis the shell is everywhere covered with pretty 
regular concentric undulations, formed by thin, rather sharp, raised 
. lines, separated by regular concave intervals ; anteriorly the ridges 
become less evident and very close; small, but distinct, radiating 
striz cross the ridges over the central parts of the shell and are deeper 
or incised in crossing the summits of the ridges; anteriorly the 
radiating striz entirely disappear; toward the posterior end they be- 
come stronger and on the posterior area they are gradually replaced 
by elevated radii which in crossing the concentric lines produce a 
distinctly granulated appearance. 
The inner surface is nearly smooth and somewhat lustrous, but 
sometimes minutely radially striated. The muscular scars are small, 
but distinct. 
Length of the largest specimens, including epidermis, 22™™" ; with- 
out the epidermis, 19"; height from beak to ventral margin, 17"™ ; 
length of dorsal margin, 9™™" ; transverse breadth, 10™™, 
Station 2228, in 1,582 fathoms, two living specimens (No. 44,822) ; 
and station 2221, in 1,525 fathoms. One dead specimen (No. 40,498.) 
This shell is larger, more oblique, and has a thinner hinge-plate 
than the form described and figured by Jeffreys. Whether it be 
identical with the original fossil shell, described by Brocchi, may be 
questionable. 
Limopsis plana Verrill, sp. nov. 
Shell rather large for the genus, broad, moderately compressed, 
decidedly oblique, with a thin, straight hinge-margin and a wide, 
elongated fusiform ligamental area, interrupted in the middle by a 
large, triangular cartilage-pit. The straight dorsal margin is less 
than one-fifth the circumference of the shell, and does not extend so 
far forward as the convexly rounded anterior margin; the ventral 
margin is regularly rounded and considerably produced backward ; 
